Mobile communication device

ABSTRACT

There is provided with a portable communication device which can perform proximity contactless communication without reducing a distance capable of performing the proximity contactless communication thereby to improve convenience and prevent degradation of the characteristics of the proximity contactless communication. 
     In a mobile communication device  1  with a proximity contactless communication function, antennas  14 A to  14 C for performing the proximity contactless communication with an external proximity contactless communication device  2  are provided on the plural surfaces of the casing  10  of the mobile communication device  1 . Each of the antennas  14 A to  14 C has one or more loops and the antennas  14 A to  14 C are coupled in series.

TECHNICAL FIELD

The present invention relates to a portable communication device havinga proximity contactless communication function.

BACKGROUND ART

Recently, there has been increasing demands for developing acommunication system which can copy electric data containing personalinformation such as data of a telephone book and store into a mobilephone, or which makes it possible to read and write electric medicalsheets at a hospital or a pharmacy, or which makes it possible to reador request electronic resident register data such as certificates ofresidence and family registers, or which can transfer, copy and storedata relating to personal hobby (various kinds of data such as music andimages) to and in an own mobile phone, etc., or which can read and storeamount of money data for a prepaid of an automatic vending machine, etc.in a desired electronic device, or which can be used as a pass, etc. forpassing through a wicket at an amusement park or a station, etc. Inother words, there has been increasing demands for developing thecommunication system (hereinafter called as a proximity contactlesscommunication system) which is made in contact to or brought close so asto be contactable to a communication partner thereby to perform acommunication (to be concretely, by using the action of electric fieldor magnetic field).

To this end, there has been investigated as to the developments ofvarious kinds of portable communication devices each having a proximitycontactless communication function (hereinafter called as “a portablecommunication device with a proximity contactless communicationfunction”), each of which can perform the proximity contactlesscommunication with a proximity contactless communication device disposedoutside (hereinafter called as “an external proximity contactlesscommunication device”) or a proximity contactless communication carddisposed outside (hereinafter called as “an external proximitycontactless communication card”) which serves a partner side at the timeof performing the proximity contactless communication (see patentdocument 1, for example).

As one of the portable communication devices accorded to such theproximity contactless communication system, there is proposed a mobilephone 100 with the proximity contactless communication function as shownin FIG. 16, for example.

As shown in the figure, the mobile phone 100 with the proximitycontactless communication function is configured in a manner that acasing 101 is formed in a straight shape (of course, a fordable shapemay be used) and contains therein not only an antenna 102 for the mobilephone for transmitting and receiving a signal to and from a base stationdisposed outside of the figure but also an antenna 103 for the proximitycontactless communication for performing the proximity contactlesscommunication with an external proximity contactless communicationdevice 200, etc.

On the other hand, the external proximity contactless communicationdevice 200 includes an antenna 201 for the proximity contactlesscommunication for performing the proximity contactless communication.

Incidentally, in the figure, a symbol 106 depicts a battery chamberwhich houses a battery unit 105 for feeding therein and is closed by abattery lid 104.

The mobile phone 100 with the proximity contactless communicationfunction is configured so as to perform communication or datacommunication with a base station via the antenna 102 for the mobilephone. The mobile phone 100 is also configured so as to perform theproximity contactless communication between the antenna 103 for theproximity contactless communication within the casing 101 of the mobilephone 100 and the antenna 201 for the proximity contactlesscommunication within the casing of the external proximity contactlesscommunication device 200 when the antenna 103 for the proximitycontactless communication provided near the one surface (the uppersurface in FIG. 16) within the casing 101 of the mobile phone 100 ismade in contact to or brought close to and placed over the externalproximity contactless communication device 200.

However, in the mobile phone 100 with the proximity contactlesscommunication function, as described above, the antenna 103 for theproximity contactless communication is disposed at the one surface ofthe casing 101 of the mobile phone 100. Thus, in the case of performingthe proximity contactless communication, when the surface other than theone surface of the casing 101 is made in contact to or brought close toand placed over the device, it is often the case that proximitycontactless communication error arises due to the directivity of theantenna 103 for the proximity contactless communication. As a result,there is a problem that the convenience is not good in a point that theparticular surface of the casing 101 is required to be placed over thedevice.

Therefore, as described in a patent document 2, for example, there isproposed such a structure that two antennas for proximity contactlesscommunication are provided in parallel to each other so that theproximity contactless communication can be performed without beinglimited to the one surface. However, according to such a configuration,since the antennas are provided in parallel to each other, the totalinductance value of the antennas decreases. In this case, in order toresonate the antenna at a desired frequency, it is necessary to increasethe inductance component of the antenna or to increase the constantvalue of a resonance capacitor.

In general, in order to increase the inductance component of theantenna, it is necessary to increase the area of the antenna andincrease the number of turns of a conductor constituting the antenna.However, it is difficult to increase the areas of the plural antennas ina small-sized communication device such as the portable communicationdevice. Further, when the constant value of the resonance capacitor ismade large, there arises a problem that the gain of the antenna forproximity contactless communication reduces and so a distance capable ofperforming the proximity contactless communication reduces.

Thus, as shown in a patent document 3 and a patent document 4, forexample, when the antenna for proximity contactless communication isconfigured in an L-shape, the proximity contactless communication can beperformed as to two surfaces or more without being limited to onesurface without reducing the inductance value of the antenna.

However, according to such a configuration, with respect to only onesurface, in the case of performing the proximity contactlesscommunication by placing this surface in parallel to the antennal of theexternal proximity contactless communication device, since there is noantenna at the corner portion of the L-shape, the magnetic flux densityat the one surface is reduced as compared with the case where theantenna loop is configured by only one surface. As a result, therearises a problem that a distance capable of performing the proximitycontactless communication reduces.

Thus, as described in a patent document 5, for example, when an antennafor proximity contactless communication is formed in a loop shape ateach of six surfaces, the proximity contactless communication can beperformed at not only one surface but also the respective surfaces.Simultaneously, when considering each one of the respective surfaces,since the each surface forms the loop, the reduction of the magneticflux density can be prevented and the distance capable of performing theproximity contactless communication can be maintained effectively.

However, according to this configuration, when the antennas at theplural surfaces are influenced by the magnetic fluxes, the currentsgenerated at the respective antennas flow in opposite directions and sothere arise a problem that the proximity contactless communication erroroccurs.

-   Patent document 1: JP-A-2002-236901 (page 2, right column, [0002])-   Patent document 2: JP-A-2001-28037-   Patent document 3: JP-A-08-44833-   Patent document 4: JP-A-11-316806-   Patent document 5: JP-A-2001-319206

DISCLOSURE OF THE INVENTION Problems that the Invention is to Solve

The invention is made in order to solve the aforesaid problems of therelated arts and an object of the invention is to provide a portablecommunication device which can perform the proximity contactlesscommunication without reducing a distance capable of performing theproximity contactless communication even by using another portion(another surface) other than a particular one surface (a communicationsurface) thereby to improve the convenience and prevent the degradationof the characteristics of the proximity contactless communication.

Means for Solving the Problems

The portable communication device according to the invention isconfigured in a manner that in the portable communication device havinga proximity contactless communication function, comprising an antennafor performing proximity contactless communication with an externalproximity contactless communication device or an external proximitycontactless communication card, the antenna being provided on aplurality of surfaces of a casing of the portable communication device,each of the antennas has at least one loop, and the antennas are coupledin series.

According to this configuration, in the case of performing the proximitycontactless communication with the external proximity contactlesscommunication device, since the antennas for the external proximitycontactless communication are disposed on the plural surfaces of thecasing of the portable communication device, the external proximitycontactless communication can be performed at a portion other than aparticular surface of the casing by placing the portable communicationdevice over the external proximity contactless communication device, forexample.

Alternatively, the portable communication device according to theinvention is configure in a manner that in the portable communicationdevice having a proximity contactless communication function, comprisingan antenna for performing proximity contactless communication with anexternal proximity contactless communication device or an externalproximity contactless communication card, the antenna being provided ona plurality of surfaces of a battery pack housed in a battery chamber ofa casing of the portable communication device or on a plurality ofsurfaces of a lid portion for closing a battery chamber providedseparately from the battery pack, each of the antennas has at least oneloop, and the antennas are coupled in series.

According to this configuration, in the case of performing the proximitycontactless communication with the external proximity contactlesscommunication device, since the antennas for the external proximitycontactless communication are disposed on the plural surfaces of thebattery pack of the portable communication device or on the pluralsurfaces of the lid portion, the external proximity contactlesscommunication can be performed at a portion other than a particularsurface of the casing by placing the portable communication device overthe external proximity contactless communication device, for example.

Alternatively, the portable communication device according to theinvention is configure in a manner that in the portable communicationdevice having a proximity contactless communication function, comprisingan antenna for performing proximity contactless communication with anexternal proximity contactless communication device or an externalproximity contactless communication card, the antenna being provided ona plurality of surfaces of a main body portion of a battery pack housedin a battery chamber of a casing of the portable communication device oron a plurality of surfaces of a lid portion which closes the batterychamber and is provided integrally with the battery pack, each of theantennas has at least one loop, and the antennas are coupled in series.

According to this configuration, in the case of performing the proximitycontactless communication with the external proximity contactlesscommunication device, since the antennas for the external proximitycontactless communication are disposed on the plural surfaces of (themain body portion of) the battery pack or on the plural surfaces of thelid portion provided integrally with the battery pack, the externalproximity contactless communication can be performed at a portion otherthan a particular surface of the casing by placing the portablecommunication device over the external proximity contactlesscommunication device, for example.

Alternatively, the portable communication device according to theinvention is configure in a manner that the electromagnetic interferencesuppression sheet is provided on the side in opposite to thecommunication surface of the antenna which opposes to the proximitycontactless communication device.

In this manner, since the electromagnetic interference suppression sheetis provided on the side in opposite to the communication surface of theantenna for the proximity contactless communication device whichperforms the proximity contactless communication.

Alternatively, the portable communication device according to theinvention further comprises an antenna for the mobile phone forperforming mobile phone communication, and an antenna feeding point forthe mobile phone, wherein the antenna for the mobile phone and theantenna feeding point are provided in separation from the antenna forthe proximity contactless communication by the required distance ormore.

According to this configuration, it is also possible to use as themobile phone. Further, since the antenna feeding point for the mobilephone is disposed so as to secure by the required distance from theantenna for the proximity contactless communication, in the case ofusing for the proximity contactless communication, the entering ofhigh-frequency radio wave (high-frequency radiation) into the antennasfor the proximity contactless communication from the antenna feedingpoint for the mobile phone can be suppressed.

EFFECTS OF THE INVENTION

According to the invention, since the small-sized antennas for theproximity contactless communication are formed on the plural surfaces asfor the portable communication device, the proximity contactlesscommunication can be performed by the plural surfaces. Further, sincethe antennas for the proximity contactless communication are disposedwithin the battery pack for the portable communication device or at thebattery lid, an advantage can be attained that the proximity contactlesscommunication can be performed on the surfaces more than the surfaces onwhich the antennas for the proximity contactless communication aredisposed.

Further, as to the portable communication device also including themobile phone function, it is possible to provide the portablecommunication device which can prevent the high-frequency componentsirradiated as the mobile phone signals from entering into the antennasfor the proximity contactless communication.

BRIEF DESCRIPTION OF THE DRAWINGS

[FIG. 1] A schematic diagram showing the configurations of the portablecommunication device according to the first embodiment of the inventionand an external proximity contactless communication device.

[FIG. 2] A development showing the pattern of the antennas for theproximity contactless communication according to the first embodiment ofthe invention.

[FIG. 3] A development showing a modified example of the pattern of theantennas for the proximity contactless communication according to thefirst embodiment of the invention.

[FIG. 4] A block diagram showing the electrical configuration of aproximity contactless communication portion according to the firstembodiment of the invention.

[FIG. 5] A development showing still another modified example of thepattern of the antennas for the proximity contactless communicationaccording to the first embodiment of the invention.

[FIG. 6] A block diagram showing the electrical configuration of theproximity contactless communication portion in the case of using anotherpattern of the antennas for the proximity contactless communicationaccording to the first embodiment of the invention.

[FIG. 7] A schematic sectional diagram of a casing showing a disposingstate of the antennas for the proximity contactless communication of theportable communication device according to the first embodiment of theinvention.

[FIG. 8] A schematic diagram showing a posture of the casing in the caseof performing the proximity contactless communication between theportable communication device according to the first embodiment of theinvention and the external proximity contactless communication device.

[FIG. 9] A schematic diagram showing another posture of the casing inthe case of performing the proximity contactless communication betweenthe external proximity contactless communication device and the portablecommunication device according to the first embodiment of the invention.

[FIG. 10] A schematic diagram showing still another posture of thecasing in the case of performing the proximity contactless communicationbetween the external proximity contactless communication device and theportable communication device according to the first embodiment of theinvention.

[FIG. 11] A schematic diagram showing the posture in the case ofperforming the proximity contactless communication by inclining thecasing of the portable communication device according to the firstembodiment of the invention.

[FIG. 12] A schematic diagram showing the posture in the case ofperforming the proximity contactless communication by inclining, in theopposite direction, the casing of the portable communication deviceaccording to the first embodiment of the invention.

[FIG. 13] A schematic diagram showing the configurations of the portablecommunication device according to the second embodiment of the inventionand the external proximity contactless communication device.

[FIG. 14] A schematic diagram showing a state in the case of performingthe proximity contactless communication between the portablecommunication device according to the third and third embodiments of theinvention and the external proximity contactless communication device.

[FIG. 15] A schematic diagram showing the configurations of the portablecommunication device according to the second embodiment of the inventionand the external proximity contactless communication device.

[FIG. 16] A schematic diagram showing the configurations of a portablecommunication device of a related art and an external proximitycontactless communication device.

DESCRIPTION OF THE REFERENCE NUMERALS AND SIGNS

-   1 portable communication device-   10 casing-   10A battery chamber-   10B battery lid-   10C upper surface-   10D lower surface-   10E step portion-   11 casing-   12 antenna for mobile phone (first antenna)-   13 antenna feeding point-   14A to 14C antenna for proximity contactless communication-   15A to 15C electromagnetic interference suppression sheet-   16 impedance matching portion-   17 control portion-   2 external proximity contactless communication device-   21 antenna-   3 battery pack (battery unit)-   4 battery pack (battery lid is provided separately)-   5 battery pack (main body portion; battery lid is provided    integrally)-   5A battery lid (lid portion)-   5B brim portion-   D1, D2 distance between the adjacent antennas for proximity    contactless communication mounted on a portable communication device-   A, B coupling portion between antenna for proximity contactless    communication and impedance matching portion of antenna for    proximity contactless communication.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, an embodiment of the invention will be explained in detailwith reference to the accompanying drawings.

First Embodiment

The explanation will be made with reference to FIGS., 1 to 12 as to amobile communication device 1 having the proximity contactlesscommunication function according to the first embodiment of theinvention and a proximity contactless communication device disposedoutside (hereinafter called as “an external proximity contactlesscommunication device”) 2.

As shown in FIG. 1, the mobile communication device 1 according to theinvention has two communication functions of the mobile phone function(a mobile phone portion) as a normal mobile phone and the proximitycontactless communication function (a proximity contactlesscommunication portion) as a portable communication device forcommunicating with the external proximity contactless communicationdevice 2. A casing 10 portion has a straight shape including not-shownoperation keys, an LCD, etc.

Although the portable communication device has the straight-shapedstructure, the present invention is not limited there to and maybeconfigured in a foldable shape.

The casing 10 includes an antenna 12 for the mobile phone (hereinaftercalled as “a first antenna”) and an antenna feeding point 13constituting a circuit dedicated to the mobile phone (the mobile phoneportion) which is mounted on a not-shown board and coupled to the firstantenna 12 and further includes a battery chamber 10A for housing abattery unit (hereinafter called as “a battery pack”) 3 therein and abattery lid 10B which closes the battery chamber 10A, etc.

Further, the casing 10 mounts therein antennas 14A to 14C for theproximity contactless communication (hereinafter called as “secondantennas”), an IC chip for the proximity contactless communicationhaving a contactless IC card function and peripheral parts, that is, animpedance matching portion 16 and a control portion 17, etc. as shown inFIGS. 4 and 6.

Although, the second antennas are configured by three antennas, thepresent invention is not limited thereto and the number of antennasconstituting the second antennas may be two or more.

On the other hand, the external proximity contactless communicationdevice 2 is disposed at the wicket of a station or a tollgate of a tollroad, etc., for example (of course, not limited thereto), and performsthe proximity contactless communication with the device having theproximity contactless communication function. To this end, within theexternal proximity contactless communication device 2, there is disposedan antenna 21 for the proximity contactless communication at a positioncloser to a surface (a portion corresponding to the lower surface inFIG. 1, which is hereinafter called as “a communication surface”)opposing to the mobile communication device 1.

The “proximity contactless communication” means a communicationperformed by using an electric field or a magnetic field as described inthe “background art”. As is well known, the magnetic force and theelectric force are kinds of force according to the Coulomb's law andhave a feature that they are reversely proportional to the square of thedistance (according to the inverse square law), the force reducesrapidly in a short range. Thus, the “proximity contactlesscommunication” in the invention represents a communication which isrealized in a proximity region mainly about 10 cm or less within whichthe electric field or the magnetic field acts.

Next, the aforesaid two kinds of antennas will be mainly explained indetail.

The first antenna 12 is a normal antenna for a mobile phone.Communication or data communication is performed with a not-shown basestation by the first antenna 12.

On the other hand, the second antennas 14A (A antenna) 14B (B antenna)and 14C (C antenna) are disposed within the casing 10 so as to beseparated from the first antenna 12 by such a required distance that theentering of high-frequency radio wave (high-frequency radiation) intothe antennas for proximity contactless communication from the antennafeeding point for the mobile phone can be suppressed.

Further, in the invention, the second antennas are disposed within thecasing 10 so as to be closer as possible to the outer surfaces(proximity contactless communication surfaces) opposing to the externalproximity contactless communication device 2 (the A antenna 14A isdisposed on the upper surface, the B antenna 14B is disposed closer tothe nearer surface side, and the C antenna 14C is disposed closer to theinner portion/rear surface side in FIG. 1) so that the proximitycontactless communication can be performed surely between the antenna 21for the proximity contactless communication of the external proximitycontactless communication device 2 and the second antennas via theproximity contactless communication surface.

In particular, as shown in FIGS. 2 and 3, the A antenna 14A, the Bantenna 14B and the C antenna 14C for the proximity contactlesscommunication are configured in a manner that the plural antennas aredrawn and formed in one-stroke manner on a sheet so that one or moreloops are formed on each surface, then the sheet is folded along each ofdotted lines so as to dispose these antennas within the casing 10 (onthe inner walls of the casing), and the respective antennas are coupledin series as shown in a block diagram of FIG. 4.

Further, as shown in FIG. 5, the A antenna 14A to the C antenna 14C arerespectively formed on the plural sheets so that the each antenna forthe proximity contactless communication is configured by one or moreloops, and the respective antennas are disposed within the casing 10.Further, as shown by a block diagram of FIG. 6, these antennas may becoupled in series. In this case, concerning the coupling state ofterminals 141 to 144 on FIGS. 5 and 6, the terminal 141 is coupled tothe terminal 142 and the terminal 143 is coupled to the terminal 144. Solong as the A antenna 14A, the B antenna 14B and the C antenna 14C arecoupled in series as shown in FIG. 6, this coupling method may bearranged in such a manner that these antennas are mounted on a not-shownboard. In brief, these antennas may be coupled by any method so long asthe A antenna 14A to the C antenna 14C are coupled in series.

According to the mobile communication device 1 configured in thismanner, since the A antenna 14A to the C antenna 14C serving as thesecond antennas for the proximity contactless communication are coupledin series as shown in FIG. 4 or 6, the inductance value of the entiretyof the second antennas becomes a total value of the inductance values ofthe respective antennas. Thus, an inductance value necessary forresonating by the entirety of the antennas for the proximity contactlesscommunication can be obtained by a small-sized terminal such as thecommunication device of the embodiment.

Further, in the casing 10 of the embodiment shown in FIG. 1, as shown inFIG. 7 which is a sectional diagram of the casing 10, electromagneticinterference suppression sheets 15A, 15B, 15C are disposed near surfaceson the opposite sides of the proximity contactless communicationsurfaces of the A antenna 14A, the B antenna 14B and the C antenna 14Cserving as the second antennas, respectively.

Thus, according to the embodiment, as shown in FIGS. 8 to 10, even in acase of performing the proximity contactless communication with theexternal proximity contactless communication device 2 by using one ofthe three surfaces as the proximity communication surface, thetransmission and reception of communication signals can be performedsurely so long as the distance is within a required range.

Further, even in a case of performing the proximity contactlesscommunication with the external proximity contactless communicationdevice 2 by placing the casing 10 of the mobile communication device 1(a sectional diagram of the casing 10 shown in FIG. 1) in a slantedstate as shown in FIGS. 11 and 12, it is sufficient to form the pluralsecond antennas as shown in FIG. 2 or 3.

That is, supposing that distances between the adjacent antennas are D1and D2 as shown in FIG. 2 or 3, although the distance changes dependingon the pattern width or an area of an opening, when at least 1 mm ormore is secured as this distance, currents flow in the same direction asfor all of the second antennas when magnetic fluxes pass from the frontsurface side to the rear surface side of the sheet in FIG. 2 or 3. Thus,sufficient proximity contactless communication property can be obtained.

Although the second antennas are configured as shown in FIGS. 2, 3 and 5in this embodiment, the invention is not limited thereto. That is, thesecond antennas may be wired in a manner that currents flow in the samedirection as for all of the second antennas when the casing is posturedas shown in FIGS. 11 and 12.

Therefore, in a case of performing the proximity contactlesscommunication between the mobile communication device 1 with theproximity contactless communication function and the external proximitycontactless communication device 2 as shown in FIGS. 8 to 12, the mobilecommunication device 1 receives magnetic fluxes radiated from theantenna 21 for the proximity contactless communication. In this case,proximity contactless signals (magnetic fluxes) are prevented fromleaking into the casing 10 by the electromagnetic interferencesuppression sheets 15A, 15B, 15C disposed on the rear surface sides ofthe A antenna 14A, the B antenna 14B, the C antenna 14C serving as thesecond antennas, respectively.

Thus, for example, magnetic fluxes received by the A antenna 14A (secondantenna) of FIG. 8 is shielded by the electromagnetic interferencesuppression sheet 15A, so that the magnetic fluxes passed through the Aantenna 14A can be prevented from reaching the B antenna 14B and the Cantenna 14C as the other second antennas.

Further, when the second antennas are wound in a manner as shown in FIG.2, 3 or 5, sufficient proximity contactless communication property canbe obtained without flowing a reverse current at the respective secondantennas.

Furthermore, even if the second antennas 14A to 14C are disposed nearthe antenna feeding point 13 of the first antenna 12 serving as theantenna for the mobile phone as shown in FIG. 1, since theelectromagnetic interference suppression sheets 15A to 15C are disposedon the rear surface sides of the second antennas 14A to 14C,respectively, as shown in FIG. 7, the high-frequency componentsirradiated as the mobile phone signals are prevented from entering intothe second antennas 14A to 14C. Thus, the stable proximity contactlesscommunication can be performed.

Second Embodiment

Next, the second embodiment according to the invention will beexplained. In this embodiment, portions identical to those of the firstembodiment are referred to by the common symbols, with explanationthereof being omitted.

In this embodiment, as shown in FIG. 13, unlike the first embodiment,the second antennas 14A to 14C serving as the antennas for the proximitycontactless communication and the electromagnetic interferencesuppression sheets 15A to 15C are disposed within the main body of thebattery pack 3 for the portable communication device.

The aforesaid IC chip for the proximity contactless communication, etc.coupled to the second antennas 14A to 14C are not disposed within abattery pack 4 but within a portion of the casing 10 which is not shown.The series connection of the second antennas 14A to 14C is completedwithin the battery pack 4, so that the number of interfaces is generallysuppressed to two although it is four depending on the function.

In this manner, since the number of the interfaces can be reduced to twofrom six in the related art, the reliability can be improved. Further,since only the second antennas 14A to 14C and the electromagneticinterference suppression sheets 15A to 15C are disposed within thebattery pack, the thickness of the battery portion (total thickness ofthe battery pack 4 and the battery lid 10B) of the casing 10 can besuppressed to be larger by 1 mm or less than that of the battery portionof the portable communication device having no proximity contactlesscommunication function.

Further, in this embodiment, since the second antennas 14A to 14C forthe proximity contactless communication and the electromagneticinterference suppression sheets 15A to 15C are disposed on the threesurfaces (of course, the invention is not limited thereto and they maybe disposed on two surfaces or four or more surfaces), due to thepresence of these electromagnetic interference suppression sheets 15A to15C, the proximity contactless communication can be performedsufficiently by the plural surfaces without flowing the reverse currentsin the respective antennas 14A to 14C. Further, the high-frequencycomponents irradiated as the mobile phone signals can be prevented fromentering into the second antennas 14A to 14C for the proximitycontactless communication.

Furthermore, in this embodiment, since the battery portion (battery pack4) for the mobile communication device is disposed at the position awayfrom the first antenna 12 for the mobile phone and the antenna feedingpoint 13, they are inevitably separately to each other, so that thehigh-frequency components irradiated as the mobile phone signals can beprevented further surely from entering into the second antennas 14A to14C. Thus, the further stable proximity contactless communication can beperformed.

Furthermore, when the battery portion (battery pack 4) for the mobilecommunication device is disposed so as to have the positional relationaway from the first antenna 12 for the mobile phone and the antennafeeding point 13, the battery chamber 10A housing the battery portion isdisposed on anther surface of the casing different from the surface ofthe casing on which the first antenna 12 is disposed. Thus, the firstantenna does not protrude from the surface of the casing on which thebattery chamber 10A is mounted.

Accordingly, the proximity contactless communication can be performed ina state that one of the surfaces of the casing on which the secondantennas 14A to 14C are disposed is brought close to the externalproximity contactless communication device 2 without being interfered bya projection such as the first antenna 12. However, as shown in FIG. 14,the casing maybe placed over the external proximity contactlesscommunication device 2 in a state that the surface 10D of the casing(the lower surface in opposite to an upper surface 10C where the firstantenna 12 is disposed) which is not one of the surfaces on which thesecond antennas 14A to 14C are disposed is brought close to the externalproximity contactless communication device 2.

That is, in such a state shown in FIG. 14, although the mobilecommunication device 1 is not placed in a positional relation inparallel to the antenna 21 for the proximity contactless communicationof the external proximity contactless communication device 2, theproximity contactless communication can be performed by one of thesecond antennas 14A to 14C for the proximity contactless communicationwithin the battery pack 4. In other words, even when the second antennasare disposed only on the three surfaces of the battery pack 4, theproximity contactless communication can be substantially performed bythe four surfaces (also by the lower surface 10D).

Further, in this embodiment, only the second antennas 14A to 14C and theelectromagnetic interference suppression sheets 15A to 15C are disposedwithin the battery pack 4, and the IC chip for the proximity contactlesscommunication coupled to the second antennas 14A to 14C are disposedwithin the portion of the casing 10 which is not shown, as describedabove. Thus, even if the battery pack 4 is lost and picked up by a thirdparty, the battery pack 4 can not be abused by the third party. That is,the safety can be secured sufficiently with respect to the securitywithout taking complicated measures of software. Further, the proximitycontactless communication function can be restored again by using thebattery pack 4 as a replacement.

Further, in this embodiment, the second antennas 14A to 14C for theproximity contactless communication and the electromagnetic interferencesuppression sheets 15A to 15C are disposed on the plural surfaces of thebattery pack 4 housed in the battery chamber 10A. In contrast, in placeof the battery pack 4, they may be disposed on the plural surfaces ofthe battery lid 10B, for example, which closes the battery chamber 10Ahousing the battery pack 4 therein.

Third Embodiment

Next, the third embodiment according to the invention will be explained.In this embodiment, portions identical to those of the first and secondembodiments are referred to by the common symbols, with explanationthereof being omitted.

In this embodiment, unlike the first and second embodiments, as shown inFIG. 15, the second antennas 14A to 14C for the proximity contactlesscommunication and the electromagnetic interference suppression sheets15A to 15C are disposed within a battery lid (this is called as “a lidportion”) 5A which is integrated with (the main body portion of) abattery pack 5 for the potable communication device.

As shown in FIG. 15, the battery pack 5 is configured in a manner thatthis battery pack is provided with a brim portion 5B protruding in thetransverse direction at the upper surface of the main body of thebattery pack 5 so that this brim portion is stopped in a state of beingengaged with a step portion 10E provided along the opening portion ofthe battery chamber 10A.

Further, also in this embodiment, like the second embodiment, thenot-shown IC chip for the proximity contactless communication coupled tothe second antennas 14A to 14C within the lid portion 5A are disposedwithin the casing 10, whereby the number of interfaces can be suppressedto two due to the series connection of the second antennas 14A to 14C.

Thus, like the second embodiment, the reliability can be improved, andfurther the thickness of the battery portion (battery pack 5) can besuppressed to be larger by 1 mm or less than that of the battery portionof the portable communication device having no proximity contactlesscommunication function.

Further, also in this embodiment, like the second embodiment, due to thepresence of these electromagnetic interference suppression sheets 15A to15C, the proximity contactless communication can be performedsufficiently by the plural surfaces without flowing the reverse currentsin the respective antennas 14A to 14C. Further, the high-frequencycomponents irradiated as the mobile phone signals can be prevented fromentering into the second antennas 14A to 14C.

Further, also in this embodiment as shown in FIG. 14, like the secondembodiment, even when none of the second antennas 14A to 14C of themobile communication device 1 are placed in a positional relation inparallel to the antenna 21 for the proximity contactless communicationof the external proximity contactless communication device 2, theproximity contactless communication can be performed by one of thesecond antennas 14A to 14C for the proximity contactless communicationwithin the lid portion 5A of the battery pack 5. Thus, the proximitycontactless communication can be performed by the four surfaces.

Furthermore, also in this embodiment, like the second embodiment, onlythe second antennas for the proximity contactless communication and theelectromagnetic interference suppression sheets are disposed within thelid portion 5A of the battery pack 5, and the IC chip for the proximitycontactless communication coupled to the second antennas 14A to 14C aredisposed within the portion of the casing 10 which is not shown. Thus,the safety can be secured sufficiently with respect to the securitywithout taking complicated measures of software.

Further, also in this embodiment, the proximity contactlesscommunication function can be restored again by using the battery pack 5as a replacement.

Although this embodiment is configured in a manner that the secondantennas 14A to 14C for the proximity contactless communication and theelectromagnetic interference suppression sheets 15A to 15C are disposedon the plural surfaces of the lid portion 5A which is integrated with(the main body portion of) the battery pack 5, they may be provided noton the lid 5A side but on (the main body portion side of) the batterypack 5.

Further, the invention is not limited to the aforesaid embodiments andcan be implemented in various modes within a scope not departing fromthe gist thereof. For example, in each of the embodiments, although theexplanation is made as an example that the communication partner of thesecond antennas 14A to 14C for the proximity contactless communicationis the external proximity contactless communication device 2, theinvention is not limited thereto. The invention maybe applied to asystem which is configured to perform the proximity contactlesscommunication with an external proximity contactless communication card.

Although the invention is explained in detail and with reference to theparticular embodiments, it will be apparent for those skilled in the artthat various changes and modifications can be made without departingfrom the spirit and scope of the invention.

The present application is based on Japanese Patent Application No.2003-393559 filed on Nov. 25, 2003, the content of which is incorporatedherein by reference.

INDUSTRIAL APPLICABILITY

The portable communication device according to the invention has theadvantages that the small-sized antenna for the proximity contactlesscommunication can be formed for the portable communication device, theproximity contactless communication can be performed by the pluralsurfaces and the high-frequency components irradiated as the mobilephone signals can be prevented from entering into the antennas for theproximity contactless communication. Further, the portable communicationdevice according to the invention is useful not only for the portablecommunication device dedicated for the proximity contactlesscommunication but also for various kinds of portable communicationdevices each having the proximity contactless communication function,for example, a mobile phone, a PHS, a PDA, etc.

1. A portable communication device having a contactless communicationfunction, comprising: a plurality of loop antennas for performingcontactless communication with an external contactless communicationdevice or an external contactless communication card, each of the loopantennas being provided on a plurality of surfaces of a casing of theportable communication device, wherein each of the loop antennascomprises at least one loop, and wherein the loop antennas are connectedin series.
 2. The portable communication device according to claim 1,further comprising: a plurality of electromagnetic interferencesuppression sheets, wherein each of the electromagnetic interferencesuppression sheets are placed, from each of the loop antennas, atopposite sides or near opposite sides of a communication surface facingexternal contactless communication device or an external contactlesscommunication card.
 3. The portable communication device according toclaim 1, further comprising: an antenna for a mobile phone forperforming mobile phone communication; and an antenna feeding point forthe mobile phone, wherein the antenna for the mobile phone and theantenna feeding point are placed in separation from the loop antennas bya required distance or more.
 4. A portable communication device having acontactless communication function, comprising: a plurality of loopantennas for performing contactless communication with an externalcontactless communication device or an external contactlesscommunication card, each of the loop antennas being provided on aplurality of surfaces of a battery pack housed in a battery chamber of acasing of the portable communication device or on a plurality ofsurfaces of a lid portion for closing a battery chamber providedseparately from the battery pack, wherein each of the loop antennascomprises at least one loop, and wherein the loop antennas are connectedin series.
 5. The portable communication device according to claim 4,further comprising: a plurality of electromagnetic interferencesuppression sheets, wherein each of the electromagnetic interferencesuppression sheets are placed, from each of the loop antennas, atopposite sides or near opposite sides of a communication surface facingexternal contactless communication device or external contactlesscommunication card.
 6. The portable communication device according toclaim 4, further comprising: an antenna for a mobile phone forperforming mobile phone communication; and an antenna feeding point forthe mobile phone, wherein the antenna for the mobile phone and theantenna feeding point are placed in separation from the loop antennasfor the contactless communication by a required distance or more.
 7. Aportable communication device having a contactless communicationfunction, comprising: a plurality of loop antennas for performingcontactless communication with an external contactless communicationdevice or an external contactless communication card, each of the loopantennas being provided on a plurality of surfaces of a main bodyportion of a battery pack housed in a battery chamber of a casing of theportable communication device or on a plurality of surfaces of a lidportion which closes the battery chamber and is provided integrally withthe battery pack, wherein each of the loop antennas comprises at leastone loop, and wherein the loop antennas are connected in series.
 8. Theportable communication device according to claim 7, further comprising:a plurality of electromagnetic interference suppression sheets, whereineach of the electromagnetic interference suppression sheets are placed,from each of the loop antennas, at opposite sides or near opposite sidesof a communication surface facing external contactless communicationdevice or an external contactless communication card.
 9. The portablecommunication device according to claim 7, further comprising: anantenna for a mobile phone for performing mobile phone communication;and an antenna feeding point for the mobile phone, wherein the antennafor the mobile phone and the antenna feeding point are placed inseparation from the loop antennas by a required distance or more.